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Evaluations of the benefits of using a mixed MEA/MDEA solvent for CO 2 capture in terms of the heat requirement for solvent regeneration, lean and rich loadings, CO 2 production, and solvent stability were performed by comparing the performance of aqueous 5 kmol/m 3 MEA with that of an aqueous 4:1 molar ratio MEA/MDEA blend of 5 kmol/m 3 total amine concentration as a function of the operating time. The tests were performed using two pilot CO 2 capture plants of the International Test Centre for CO 2 Capture (ITC), which provided two different sources and compositions of flue gas. The University of Regina CO 2 plant (UR unit) processes flue gas from the combustion of natural gas while the Boundary Dam CO 2 plant (BD unit) processes flue gas from a coal-fired electric power station. The results show that a huge heat-duty reduction can be achieved by using a mixed MEA/MDEA solution instead of a single MEA solution in an industrial environment of a CO 2 capture plant. However, this benefit is dependent on whether the chemical stability of the solvent can be maintained.

The product distribution obtained from the thermal cracking of canola oil was studied at atmospheric pressure in a fixed-bed reactor in the temperature range 300-500°C and gas hourly space velocity (GHSV) in the range 3.3-640 h -1 over inert materials and in the presence and absence of steam. Results showed that canola oil conversions were high (54-100 wt %) and depended strongly on the operating variables. Products essentially consisted of C 4 and C 5 hydrocarbons, aromatic and C 6 + aliphatic hydrocarbons, and C 2 -C 4 olefins, as well as a diesellike fuel fraction and hydrogen. GC-MS analyses showed that product distribution as well as the lengths of the carbon chain of hydrocarbons and oxygenated hydrocarbons depended strongly not only on the cracking temperature and space velocity but also on whether cracking was conducted in the presence or absence of steam. On the other hand, cracking over inert materials showed that both conversion and product distribution were completely independent of morphology of the cracking surface. A reaction scheme has been proposed to account for the product distribution obtained from the thermal cracking of canola oil. The observed changes in both canola oil conversion and product distribution with changes in the operating variables were found to be consistent with the reaction scheme.

Please cite this article in press as: Liang, Z., et al., Recent progress and new developments in post-combustion carbon-capture technology with amine based solvents. Int. J. Greenhouse Gas Control (2015), http://dx.Keywords: Recent development of PCC process Design and modeling Solvent development Post Build Operations Solvent chemistry Solvent management Mass transfer with reaction a b s t r a c tCurrently, post-combustion carbon capture (PCC) is the only industrial CO 2 capture technology that is already demonstrated at full commercial scale in the TMC Mongstad in Norway (300,000 tonnes per year CO 2 captured) and BD3 SaskPower in Canada (1 million tonnes per year CO 2 captured). This paper presents a comprehensive review of the most recent information available on all aspects of the PCC processes. It provides designers and operators of amine solvent-based CO 2 capture plants with an in-depth understanding of the most up-to-date fundamental chemistry and physics of the CO 2 absorption technologies using amine-based reactive solvents. Topics covered include chemical analysis, reaction kinetics, CO 2 solubility, and innovative configurations of absorption and stripping columns as well as information on technology applications. The paper also covers in detail the post build operational issues of corrosion prevention and control, solvent management, solvent stability, solvent recycling and reclaiming, intelligent monitoring and plant control including process automation. In addition, the review discusses the most up-to-date insights related to the theoretical basis of plant operation in terms of thermodynamics, transport phenomena, chemical reaction kinetics/engineering, interfacial phenomena, and materials. The insights will assist engineers, scientists, and decision makers working in academia, industry and government, to gain a better appreciation of the post combustion carbon capture technology.

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The performance of a hybrid solid acid catalyst consisting of a physical mixture of γ‐Al2O3 and H‐ZSM‐5 in terms of the rate and heat duty for solvent regeneration (i.e., CO2 stripping) of a CO2‐rich MEA solution was compared with the individual performance of γ‐Al2O3, H‐ZSM‐5, and H‐Y solid acid catalysts using MEA (2–7 mol/L), with initial CO2 loading of 0.5 mol CO2/mol MEA at 378 K. It was observed that any catalyst significantly decreased the energy required for CO2 regeneration. The performance of the catalysts investigated ranked as follows: γ‐Al2O3/H‐ZSM‐5 = 2/1 > γ‐Al2O3 > H‐ZSM‐5 > H‐Y if the process is in the lean CO2 loading region whereas it was H‐ZSM‐5 > γ‐Al2O3/H‐ZSM‐5 = 2/1 > γ‐Al2O3 > H‐Y if the process is in the rich CO2 loading region. These results highlight the joint dependence on Brønsted/Lewis acidity and mesopore surface area of heat duty for solvent regeneration. © 2015 American Institute of Chemical Engineers AIChE J, 62: 753–765, 2016

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Carbon dioxide reforming of methane (CDRM) was studied over a variety of ZrO 2 -, ceria-doped ZrO 2 -, and CeO 2 -ZrO 2 -supported Ni catalysts. Different techniques were used to prepare supports material having different physicochemical properties, and a correlation was established to show the importance of a robust support material. Various characterization of the catalyst further established that the coking behavior of the catalyst depends on the support preparation techniques. Compared to zirconia and ceria-doped zirconia, the use of ceria-zirconia (Ce x Zr 1-x O 2 ) solid solution as a support prepared by using a surfactant was found to be the most stable for low-temperature CDRM. It seems the inhibition of reactions leading to carbon deposition is prominent in systems having ZrO 2 . Temperature-programmed oxidation (TPO) experiments indicated excellent resistance toward carbon formation for Ni supported on Ce x Zr 1-x O 2 compared with other catalysts studied. H 2 -TPR (temperature-programmed reduction) analyses also showed that the stability of Ce x Zr 1-x O 2 solid solution is a function of its enhanced reducibility at lower temperatures as compared to either pure ceria or ceria-doped ZrO 2 . Based on all the catalysts studied, 5% Ni Ce 0.6 Zr 0.4 O 2 was found to be the best catalyst as activity was stable for up to 100 h at 650 and 700 °C, while at 800 °C the catalyst activity remained stable for more than 200 h.